This invention relates to an automatic control for the switch motor of electromechanical, self-stabilizing balances provided with electromagnetic compensation. The invention relates more particularly to such balances from whose analog transducer an analog measured value, which triggers the operation of a switching motor, when an upper or lower limiting value is exceeded, can be supplied to a display device.
An automatic control circuit of this type is known from German Pat. No. 2,131,058. In this known control circuit, the analog measured value is fed to a digital voltmeter. Switches in the digital voltmeter are arranged to correspond to the limits of the display measurement range of this digital voltmeter. If these limits are reached or exceeded, these switches are closed after a delay of 2.5 seconds by a delay switching member which is a part of the digital voltmeter, triggering a switch weight adjustment device after a delay. A second delay is provided which disables the adjusting device for a specified delay of 2.5 seconds after the weights are switched. If the measured weight exceeds limits far beyond the original limits, this second delay can be cut out, but the first delay of 2.5 seconds, associated with the digital voltmeter, and lasting until switching is performed after a limiting value is reached, is retained. This known automatic switch weight adjustment device consequently has a measurement rate limit which cannot be taken into account in measuring processes which must be carried out frequently, especially in automated processes.